1
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Lorkowski J, Yorkgitis P, Serrato MR, Gembicky M, Pietraszuk C, Bertrand G, Jazzar R. Genuine carbene versus carbene-like reactivity. Angew Chem Int Ed Engl 2024; 63:e202401020. [PMID: 38632078 DOI: 10.1002/anie.202401020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Revised: 04/14/2024] [Accepted: 04/17/2024] [Indexed: 04/19/2024]
Abstract
Singlet carbenes are not always isolable and often even elude direct detection. When they escape observation, their formation can sometimes be evidenced by in situ trapping experiments. However, is carbene-like reactivity genuine evidence of carbene formation? Herein, using the first example of a spectroscopically characterized cyclic (amino)(aryl)carbene (CAArC), we cast doubt on the most common carbene trapping reactions as sufficient proof of carbene formation.
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Affiliation(s)
- Jan Lorkowski
- UCSD-CNRS Joint Research Chemistry Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA-92093-0343, USA
| | - Patrick Yorkgitis
- UCSD-CNRS Joint Research Chemistry Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA-92093-0343, USA
| | - Melinda R Serrato
- UCSD-CNRS Joint Research Chemistry Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA-92093-0343, USA
| | - Milan Gembicky
- UCSD-CNRS Joint Research Chemistry Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA-92093-0343, USA
| | - Cezary Pietraszuk
- Faculty of Chemistry, Adam Mickiewicz University, Poznań, Uniwersytetu Poznańskiego 8, 61-614, Poznań, Poland
| | - Guy Bertrand
- UCSD-CNRS Joint Research Chemistry Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA-92093-0343, USA
| | - Rodolphe Jazzar
- UCSD-CNRS Joint Research Chemistry Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA-92093-0343, USA
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2
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Maltz L, Gabbaï FP. Exploring the Effects of Se Basicity on a Te···Se Interaction Supported by a Rigid Indazolium Backbone. Organometallics 2024; 43:1246-1255. [PMID: 38873571 PMCID: PMC11167644 DOI: 10.1021/acs.organomet.4c00094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Revised: 04/19/2024] [Accepted: 04/26/2024] [Indexed: 06/15/2024]
Abstract
With an interest in chalcogen bonding, we use a rigid indazolium backbone to install a formally zero-valent Se center next to a divalent Te center, allowing us to investigate the effects of oxidation of the Se center on the observed Te···Se interaction. Through spectroscopic and computational comparison of the Se(0) species with its Se(II) counterpart and their monochalcogen analogues, we experimentally and computationally investigate the effect of modulating Se basicity on the resulting Te···Se interaction. Comparison with well-studied naphthalene and acenaphthene variants indicates that the increased basicity of the Se(0) center allows for a comparably strong Te···Se interaction despite longer peri distances and a larger splay angle. Finally, our study illuminates the potential non-innocence of cationic organic substituents in chalcogen-bonding catalysis of the transfer hydrogenation of quinolines.
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Affiliation(s)
- Logan
T. Maltz
- Department of Chemistry, Texas A&M University, College
Station, Texas 77843, United States
| | - François P. Gabbaï
- Department of Chemistry, Texas A&M University, College
Station, Texas 77843, United States
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3
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Magis D, Cabrera-Trujillo JJ, Vignolle J, Sotiropoulos JM, Taton D, Miqueu K, Landais Y. Expedient Synthesis of Thermally Stable Acyclic Amino(haloaryl)carbenes: Experimental and Theoretical Evidence of "Push-Pull" Stabilized Carbenes. J Am Chem Soc 2024. [PMID: 38857384 DOI: 10.1021/jacs.4c04872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2024]
Abstract
A library of novel structurally related singlet carbenes, namely, acyclic amino(haloaryl)carbenes, was designed by a high-yielding two-step procedure, and their chemical stability explored both experimentally and theoretically. Thanks to a careful selection of both the amino and the aryl substitution pattern, these carbenes exhibit a wide range of stability and reactivity, spanning from rapid self-dimerization for carbenes featuring ortho-F substituents to very high chemical stability as bare carbenes, up to 60 °C for several hours for compounds carrying ortho-Br substituents. Their structure was determined through NMR and X-ray diffraction studies, and their reactivity evaluated in benchmark reactions, highlighting the ambiphilic character of this novel class of singlet carbenes. In contrast with previously reported aryl substituents incorporating o-CF3 and t-Bu groups, which were considered "spectator", the high chemical stability of some of these carbenes relates to the stabilization of the σ-orbital of the carbene center by the π-accepting haloaryl substituent through delocalization. Kinetic protection of the carbene center is also provided by the ortho-halogen atoms, as demonstrated computationally. This push-pull stabilization effect makes acyclic amino(haloaryl) carbenes among the most ambiphilic stable carbenes reported to date, holding promise for a variety of applications.
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Affiliation(s)
- Damien Magis
- CNRS, Bordeaux INP, Institut des Sciences Moléculaires (ISM, UMR 5255), Université de Bordeaux, 351 Cours de la Libération, 33400 Talence, France
| | - Jorge Juan Cabrera-Trujillo
- E2S-UPPA, CNRS, Institut des Sciences Analytiques et de Physico-Chimie pour l'Environnement et les Matériaux (IPREM, UMR 5254), Université de Pau et des Pays de l'Adour, Hélioparc, 2 Avenue du Président Angot, 64053 Pau Cedex 09, France
| | - Joan Vignolle
- CNRS, Bordeaux INP-ENSMAC, Laboratoire de Chimie des Polymères Organiques (LCPO, UMR 5629), Université de Bordeaux, 16 Avenue Pey-Berland, 33607 Pessac Cedex, France
| | - Jean-Marc Sotiropoulos
- E2S-UPPA, CNRS, Institut des Sciences Analytiques et de Physico-Chimie pour l'Environnement et les Matériaux (IPREM, UMR 5254), Université de Pau et des Pays de l'Adour, Hélioparc, 2 Avenue du Président Angot, 64053 Pau Cedex 09, France
| | - Daniel Taton
- CNRS, Bordeaux INP-ENSMAC, Laboratoire de Chimie des Polymères Organiques (LCPO, UMR 5629), Université de Bordeaux, 16 Avenue Pey-Berland, 33607 Pessac Cedex, France
| | - Karinne Miqueu
- E2S-UPPA, CNRS, Institut des Sciences Analytiques et de Physico-Chimie pour l'Environnement et les Matériaux (IPREM, UMR 5254), Université de Pau et des Pays de l'Adour, Hélioparc, 2 Avenue du Président Angot, 64053 Pau Cedex 09, France
| | - Yannick Landais
- CNRS, Bordeaux INP, Institut des Sciences Moléculaires (ISM, UMR 5255), Université de Bordeaux, 351 Cours de la Libération, 33400 Talence, France
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4
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Farkas V, Csókás D, Erdélyi Á, Turczel G, Bényei A, Nagy T, Kéki S, Pápai I, Tuba R. "Inverted" Cyclic(Alkyl)(Amino)Carbene (CAAC) Ruthenium Complex Catalyzed Isomerization Metathesis (ISOMET) of Long Chain Olefins to Propylene at Low Ethylene Pressure. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2400118. [PMID: 38482751 PMCID: PMC11109630 DOI: 10.1002/advs.202400118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Revised: 02/20/2024] [Indexed: 05/23/2024]
Abstract
Isomerization Metathesis (ISOMET) reaction is an emerging tool for "open loop" chemical recycling of polyethylene to propylene. Novel, latent N-Alkyl substituted Cyclic(Alkyl)(Amino)Carbene (CAAC)-ruthenium catalysts (5a-Ru, 3b-Ru - 6c-Ru) are developed rendering "inverted" chemical structure while showing enhanced ISOMET activity in combination with (RuHCl)(CO)(PPh3)3 (RuH) double bond isomerization co-catalyst. Systematic investigations reveal that the steric hindrance of the substituents on nitrogen and carbon atom adjacent to carbene moiety in the CAAC ligand have significantly improved the catalytic activity and robustness. In contrast to the NHC-Ru and CAAC-Ru catalyst systems known so far, these systems show higher isomerization metathesis (ISOMET) activity (TON: 7400) on the model compound 1-octadecene at as low as 3.0 bar optimized pressure, using technical grade (3.0) ethylene. The propylene content formed in the gas phase can reach up to 20% by volume.
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Affiliation(s)
- Vajk Farkas
- Institute of Materials and Environmental ChemistryResearch Centre for Natural SciencesMagyar tudósok körútja 2BudapestH‐1117Hungary
- Department of Organic Chemistry and TechnologyBudapest University of Technology and EconomicsSzent Gellért tér 4BudapestH‐1111Hungary
| | - Dániel Csókás
- Institute of Organic ChemistryResearch Centre for Natural SciencesMagyar tudósok körútja 2BudapestH‐1117Hungary
| | - Ádám Erdélyi
- Institute of Materials and Environmental ChemistryResearch Centre for Natural SciencesMagyar tudósok körútja 2BudapestH‐1117Hungary
- Research Centre for BiochemicalEnvironmental and Chemical EngineeringDepartment of MOL Hydrocarbon and Coal ProcessingUniversity of PannoniaEgyetem u. 10VeszprémH‐8210Hungary
| | - Gábor Turczel
- Institute of Materials and Environmental ChemistryResearch Centre for Natural SciencesMagyar tudósok körútja 2BudapestH‐1117Hungary
| | - Attila Bényei
- Department of Physical ChemistryFaculty of Science and TechnologyUniversity of DebrecenEgyetem tér 1DebrecenH‐4032Hungary
| | - Tibor Nagy
- Department of Applied ChemistryFaculty of Science and TechnologyUniversity of DebrecenEgyetem tér 1DebrecenH‐4032Hungary
| | - Sándor Kéki
- Department of Applied ChemistryFaculty of Science and TechnologyUniversity of DebrecenEgyetem tér 1DebrecenH‐4032Hungary
| | - Imre Pápai
- Institute of Organic ChemistryResearch Centre for Natural SciencesMagyar tudósok körútja 2BudapestH‐1117Hungary
| | - Róbert Tuba
- Institute of Materials and Environmental ChemistryResearch Centre for Natural SciencesMagyar tudósok körútja 2BudapestH‐1117Hungary
- Research Centre for BiochemicalEnvironmental and Chemical EngineeringDepartment of MOL Hydrocarbon and Coal ProcessingUniversity of PannoniaEgyetem u. 10VeszprémH‐8210Hungary
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5
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Merschel A, Vishnevskiy YV, Neumann B, Stammler HG, Ghadwal RS. Boosting the π-Acceptor Property of Mesoionic Carbenes by Carbonylation with Carbon Monoxide. Angew Chem Int Ed Engl 2024; 63:e202318525. [PMID: 38284508 DOI: 10.1002/anie.202318525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2023] [Revised: 01/17/2024] [Accepted: 01/17/2024] [Indexed: 01/30/2024]
Abstract
We report the room temperature dimerization of carbon monoxide mediated by C4/C5-vicinal anionic dicarbenes Li(ADC) (ADC = ArC{(Dipp)NC}2 ; Dipp = 2,6-iPr2 C6 H3 ; Ar = Ph, DMP (4-Me2 NC6 H4 ), Bp (4-PhC6 H4 )) to yield (E)-ethene-1,2-bis(olate) (i.e. - O-C=C-O- = COen ) bridged mesoionic carbene (iMIC) lithium compounds COen -[(iMIC)Li]2 (COen -[iMIC]2 = [ArC{(Dipp)NC}2 (CO)]2 ) in quantitative yields. COen -[(iMIC)Li]2 are highly colored stable solids, exhibit a strikingly small HOMO-LUMO energy gap, and readily undergo 2e-oxidations with selenium, CuCl (or CuCl2 ), and AgCl to afford the dinuclear compounds COon -[(iMIC)E]2 (E = Se, CuCl, AgCl) featuring a 1,2-dione bridged neutral bis-iMIC (i.e. COon -[iMIC]2 = [ArC{(Dipp)NC}2 (C=O)]2 ). COen -[(iMIC)Li]2 undergo redox-neutral salt metathesis reactions with LiAlH4 and (Et2 O)2 BeBr2 and afford COen -[(iMIC)AlH2 ]2 and COen -[(iMIC)BeBr]2 , in which the dianionic COen -moiety remains intact. All compounds have been characterized by NMR spectroscopy, mass spectrometry, and X-ray diffraction. Stereoelectronic properties of COon -[iMIC]2 are quantified by experimental and theoretical methods.
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Affiliation(s)
- Arne Merschel
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry, Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, D-33615, Bielefeld, Germany
| | - Yury V Vishnevskiy
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry, Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, D-33615, Bielefeld, Germany
| | - Beate Neumann
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry, Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, D-33615, Bielefeld, Germany
| | - Hans-Georg Stammler
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry, Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, D-33615, Bielefeld, Germany
| | - Rajendra S Ghadwal
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry, Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, D-33615, Bielefeld, Germany
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6
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Vermersch F, Wang VT, Abdellaoui M, Jazzar R, Bertrand G. Ambiphilicity of ring-expanded N-heterocyclic carbenes. Chem Sci 2024; 15:3707-3710. [PMID: 38455021 PMCID: PMC10915854 DOI: 10.1039/d3sc04543a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Accepted: 01/18/2024] [Indexed: 03/09/2024] Open
Abstract
N-heterocyclic carbenes, such as imidazole-2-ylidenes and imidazolin-2-ylidenes, the popular class of singlet carbenes introduced by Arduengo in 1991 have not been shown to be ambiphilic owing to the two σ-withdrawing, π-donating amino groups flanking the carbene centre. However, our experimental data suggest that ring-expanded N-heterocyclic carbenes (RE-NHCs), especially the seven and eight membered rings, are significantly ambiphilic. Our results also show that the steric environment in RE-NHCs can become a determining factor for controlling the E-H bond activation.
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Affiliation(s)
- François Vermersch
- UCSD-CNRS Joint Research Chemistry Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California La Jolla San Diego California 92093-0358 USA
| | - Victor T Wang
- UCSD-CNRS Joint Research Chemistry Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California La Jolla San Diego California 92093-0358 USA
| | - Mehdi Abdellaoui
- UCSD-CNRS Joint Research Chemistry Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California La Jolla San Diego California 92093-0358 USA
| | - Rodolphe Jazzar
- UCSD-CNRS Joint Research Chemistry Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California La Jolla San Diego California 92093-0358 USA
| | - Guy Bertrand
- UCSD-CNRS Joint Research Chemistry Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California La Jolla San Diego California 92093-0358 USA
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7
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Merschel A, Vishnevskiy YV, Neumann B, Stammler HG, Ghadwal RS. Ring-Opening of 1,3-Imidazole Based Mesoionic Carbenes (iMICs) and Ring-Closing Clicks: Facile Access to iMIC-Compounds. Chemistry 2024; 30:e202303652. [PMID: 37937442 DOI: 10.1002/chem.202303652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2023] [Revised: 11/07/2023] [Accepted: 11/08/2023] [Indexed: 11/09/2023]
Abstract
Herein, ring-opening of mesoionic carbenes (iMICs) (iMIC=[ArC{N(Dipp)}2 C(SiMe3 )C:) (Dipp=2,6-iPr2 C6 H3 , Ar=Ph, 4-Me2 NC6 H4 or 4-PhC6 H4 ) based on an 1,3-imidazole scaffold to yield N-ethynylformimidamide (eFIM) derivatives as crystalline solids (eFIM={(Dipp)N=C(Ar)N(Dipp)}C≡CSiMe3 ) is reported. eFIMs are thermally stable under inert gas atmosphere and show moderate air stability (t1/2= 3 h for Ar=Ph). eFIMs are excellent surrogates of iMICs, which generally have a limited shelf-life, and readily undergo ring-closing click reactions with a variety of main-group as well as transition metal Lewis acids to form hitherto challenging iMIC-compounds in good to excellent yields. In addition to the relevance of eFIMs in the synthesis of iMIC-compounds, quantification of the stereoelectronic properties of a representative iMIC (Ar=Ph) by experimental and theoretical methods suggests remarkably σ-donor property and steric profile of these new ligand sets.
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Affiliation(s)
- Arne Merschel
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, D-33615, Bielefeld, Germany
| | - Yury V Vishnevskiy
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, D-33615, Bielefeld, Germany
| | - Beate Neumann
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, D-33615, Bielefeld, Germany
| | - Hans-Georg Stammler
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, D-33615, Bielefeld, Germany
| | - Rajendra S Ghadwal
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, D-33615, Bielefeld, Germany
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8
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Mandal C, Joshi S, Das S, Mishra S, Mukherjee D. 2-Anilidomethylpyridine-Derived Three-Coordinate Zinc Hydride: The Journey Unveils Anilide Backbone's Reactive Nature. Inorg Chem 2024; 63:739-751. [PMID: 38127496 DOI: 10.1021/acs.inorgchem.3c03673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2023]
Abstract
Low-coordinate heteroleptic zinc hydrides are catalytically important but rare and synthetically challenging. We herein report three-coordinate monomeric zinc hydride on a 2-anilidomethylpyridine framework (NNL). The synthetic success comes through systematically screening a few different routes from different precursors. During the process, the ligand's anilide backbone interestingly appears to be more reactive than Zn's terminal site to electrophilic Lewis and Brønsted acids. The proligand NNLH reacts with [Zn{N(SiMe3)2}2] and ZnEt2 to give [(NNL)ZnA] (A = N(SiMe3)2 (1), Et(2)). Both are inert to PhSiH3 and H2 but react with HBpin only through the internal Zn-Nanilide bond to give the borylated ligand NNLBpin (3). The reactions of 1 and 2 with Ph3EOH (E = C, Si) afford a series of divergent compounds like [(NNLH)Zn(OSiPh3)2] (4), [Zn3(OSiPh3)4Et2] (5), and [EtZn(OCPh3)] (6). But in all cases, it is invariably the Zn-Nanilide bond protonated by the -OH with equal or higher preference than the terminal Zn-N or Zn-C bonds. A DFT analysis rationalizes the origin of such a reactivity pattern. Realizing that an acid-free route might be the key, reacting [(NNL)Li] with ZnBr2 gives [(NNL)Zn(μ-Br)]2 (7), which on successively treating with KOSiPh3 and PhSiH3 gives the desired [(NNL)ZnH] (8) as a three-coordinate monomer with a terminal Zn-H bond. Estimating the ligand steric in 8 shows the openness in Zn's coordination sphere, a desired criterion for efficient catalysis. This and a positive influence of the pyridyl sidearm is reflected in 8's superior activity in hydroborating PhC(O)Me by HBpin in comparison to Jones' two-coordinate anilido zinc hydride.
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Affiliation(s)
- Chhotan Mandal
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, West Bengal, India
| | - Shalini Joshi
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India
| | - Sanjay Das
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, West Bengal, India
| | - Sabyashachi Mishra
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India
| | - Debabrata Mukherjee
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, West Bengal, India
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Podchorodecka P, Dziuk B, Szostak R, Szostak M, Bisz E. IPr* Oxa - a new class of sterically-hindered, wingtip-flexible N,C-chelating oxazole-donor N-heterocyclic carbene ligands. Dalton Trans 2023; 52:13608-13617. [PMID: 37698540 DOI: 10.1039/d3dt02255b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/13/2023]
Abstract
N-heterocyclic carbenes (NHCs) have emerged as a major direction in ancillary ligand development for stabilization of reactive metal centers in inorganic and organometallic chemistry. In particular, wingtip-flexible NHCs have attracted significant attention due to their unique ability to provide a sterically-demanding environment for transition metals in various oxidation states. Herein, we report a new class of sterically-hindered, wingtip-flexible NHC ligands that feature N,C-chelating oxazole donors. These ligands are readily accessible through a modular arylation of oxazole derivatives. We report their synthesis and complete structural and electronic characterization. The evaluation of steric, electron-donating and π-accepting properties and coordination chemistry to Ag(I), Pd(II) and Rh(I) is described. Preliminary studies of catalytic activity in Ag, Pd and Rh-catalyzed coupling and hydrosilylation reactions are presented. This study establishes the fluxional behavior of a freely-rotatable oxazole unit, wherein the oxazolyl ring adjusts to the steric and electronic environment of the metal center. Considering the tremendous impact of sterically-hindered NHCs and their potential to stabilize reactive metals by N-chelation, we expect that this class of NHC ligands will be of broad interest in inorganic and organometallic chemistry.
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Affiliation(s)
- Pamela Podchorodecka
- Department of Chemistry, Opole University, 48 Oleska Street, Opole 45-052, Poland.
| | - Błażej Dziuk
- Department of Chemistry, University of Science and Technology, Norwida 4/6, Wroclaw 50-373, Poland
| | - Roman Szostak
- Department of Chemistry, Wroclaw University, F. Joliot-Curie 14, Wroclaw 50-383, Poland
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102, USA.
| | - Elwira Bisz
- Department of Chemistry, Opole University, 48 Oleska Street, Opole 45-052, Poland.
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10
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Baguli S, Kundu A, Nath S, Adhikari D, Mukherjee D. A Donor-Acceptor Cyclopropane by Intramolecular C(sp 3)-H Activation at a Cyclic(alkyl)(amino)carbene Center and Its Fascinating Ring-Opening Chemistry. Org Lett 2023; 25:3141-3145. [PMID: 37093744 DOI: 10.1021/acs.orglett.3c01072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2023]
Abstract
Virtually irreversible intramolecular C-H activations are deleterious for aza-carbenes. A picolyl-tethered cyclic(alkyl)(amino)carbene (CAAC) isomerizes into a donor-acceptor cyclopropane in this manner but restores the CAAC status by retro-C-H activation in the presence of trapping agents like Se or CuCl. The same DA cyclopropane is readily hydrolyzed to a pyrrolidin-2-ol that acts as another picoCAAC precursor by undergoing 1,1-dehydration in the presence of Se or CuCl. The chemistry is distinct from the N-heterocyclic carbene analogue throughout.
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Affiliation(s)
- Sudip Baguli
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata Mohanpur, Nadia, West Bengal 741246, India
| | - Abhishek Kundu
- Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali, SAS Nagar, Manauli, Punjab 140306, India
| | - Soumajit Nath
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata Mohanpur, Nadia, West Bengal 741246, India
| | - Debashis Adhikari
- Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali, SAS Nagar, Manauli, Punjab 140306, India
| | - Debabrata Mukherjee
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata Mohanpur, Nadia, West Bengal 741246, India
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11
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Koike T, Iwamoto T. Cyclobutenylidene: A Multifaceted Two-Coordinate Carbon Species Obtained via Skeletal Editing of a Cyclopropenylidene. J Am Chem Soc 2023; 145:9264-9272. [PMID: 37040540 DOI: 10.1021/jacs.3c01906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/13/2023]
Abstract
C4H4 isomers not only serve as a basis to understand the chemical properties of hydrocarbons but are possible intermediates in combustion and organic reactions in outer space. Cyclobutenylidene (CBY), an elusive C4H4 isomer, is often proposed as a key intermediate in transition-metal-catalyzed metathesis and cycloaddition reactions between carbon-carbon multiple bonds. The geometrical structure of cyclobutenylidene predicted by calculations had been debated as whether it should be regarded as a carbocyclic carbene or a strained bridgehead alkene. Here, we report the synthesis of a crystalline cyclobutenylidene derivative, namely, a 3-silacyclobut-2-en-4-ylidene (SiCBY) via "carbene-to-carbene ring-expansion" reaction of an isolable diaminocyclopropenylidene induced by a silicon analogue of a carbene (silylene). The SiCBY exhibits multifaceted electronic properties which are corroborated by its extremely strong electron-donating properties and ambiphilic reactivity toward small gaseous molecules and C-H bonds. This result introduces an exciting strategy as well as a molecular motif to access low-valent carbon species with unusual electronic properties.
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Affiliation(s)
- Taichi Koike
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan
| | - Takeaki Iwamoto
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan
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12
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Kim H, Lee E. Ambiphilic singlet carbenes: Electron donors and acceptors. B KOREAN CHEM SOC 2022. [DOI: 10.1002/bkcs.12620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Hyunho Kim
- Department of Chemistry Pohang University of Science and Technology Pohang Republic of Korea
| | - Eunsung Lee
- Department of Chemistry Pohang University of Science and Technology Pohang Republic of Korea
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13
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Volk J, Heinz M, Leibold M, Bruhn C, Bens T, Sarkar B, Holthausen MC, Siemeling U. A crystalline cyclic (alkyl)(amino)carbene with a 1,1'-ferrocenylene backbone. Chem Commun (Camb) 2022; 58:10396-10399. [PMID: 36039867 DOI: 10.1039/d2cc03871d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Cyclic (alkyl)(amino)carbenes with a 1,1'-ferrocenylene backbone (fcCAACs) are established as an original family by the preparation of a crystalline congener. The Ccarbene bond angle is unprecedentedly wide for a CAAC, causing an exceptionally pronounced ambiphilicity. The redox-active backbone opens the door to unconventional metalloradicals and oligoradicals.
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Affiliation(s)
- Julia Volk
- Institut für Chemie, Universität Kassel, Heinrich-Plett-Straße 40, 34132 Kassel, Germany.
| | - Myron Heinz
- Institut für Anorganische und Analytische Chemie, Goethe-Universität, Max-von-Laue-Straße 7, 60438 Frankfurt am Main, Germany
| | - Michael Leibold
- Institut für Chemie, Universität Kassel, Heinrich-Plett-Straße 40, 34132 Kassel, Germany.
| | - Clemens Bruhn
- Institut für Chemie, Universität Kassel, Heinrich-Plett-Straße 40, 34132 Kassel, Germany.
| | - Tobias Bens
- Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 50659 Stuttgart, Germany
| | - Biprajit Sarkar
- Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 50659 Stuttgart, Germany
| | - Max C Holthausen
- Institut für Anorganische und Analytische Chemie, Goethe-Universität, Max-von-Laue-Straße 7, 60438 Frankfurt am Main, Germany
| | - Ulrich Siemeling
- Institut für Chemie, Universität Kassel, Heinrich-Plett-Straße 40, 34132 Kassel, Germany.
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14
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Zapf L, Peters S, Bertermann R, Radius U, Finze M. Tricyanoborane‐Functionalized Anionic N‐Heterocyclic Carbenes: Adjustment of Charge and Stereo‐Electronic Properties. Chemistry 2022; 28:e202200275. [PMID: 35535791 PMCID: PMC9401011 DOI: 10.1002/chem.202200275] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Indexed: 11/19/2022]
Abstract
The 1‐methyl‐3‐(tricyanoborane)imidazolin‐2‐ylidenate anion (2) was obtained in high yield by deprotonation of the B(CN)3‐methylimidazole adduct 1. Regarding charge and stereo‐electronic properties, anion 2 closes the gap between well‐known neutral NHCs and the ditopic dianionic NHC, the 1,3‐bis(tricyanoborane)imidazolin‐2‐ylidenate dianion (IIb). The influence of the number of N‐bonded tricyanoborane moieties on the σ‐donating and π‐accepting properties of NHCs was assessed by quantum chemical calculations and verified by experimental data on 2, IIb, and 1,3‐dimethylimidazolin‐2‐ylidene (IMe, IIa). Therefore NHC 2, which acts as a ditopic ligand via the carbene center and the cyano groups, was reacted with alkyl iodides, selenium, and [Ni(CO)4] yielding alkylated imidazoles 3 and 4, the anionic selenium adduct 5, and the anionic nickel tricarbonyl complex 8, respectively. The results of this study prove that charge, number of coordination sites, buried volume (%Vbur) and σ‐donor and π‐acceptor abilities of NHCs can be effectively fine‐tuned via the number of tricyanoborane substituents.
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Affiliation(s)
- Ludwig Zapf
- Institute for Sustainable Chemistry & Catalysis with Boron (ICB) Institute of Inorganic Chemistry Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Sven Peters
- Institute for Sustainable Chemistry & Catalysis with Boron (ICB) Institute of Inorganic Chemistry Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Rüdiger Bertermann
- Institute for Sustainable Chemistry & Catalysis with Boron (ICB) Institute of Inorganic Chemistry Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Udo Radius
- Institute for Sustainable Chemistry & Catalysis with Boron (ICB) Institute of Inorganic Chemistry Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Maik Finze
- Institute for Sustainable Chemistry & Catalysis with Boron (ICB) Institute of Inorganic Chemistry Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
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15
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Serrato MR, Melaimi M, Bertrand G. Cyclic (amino)(barrelene)carbenes: an original family of CAACs through a novel synthetic pathway. Chem Commun (Camb) 2022; 58:7519-7521. [PMID: 35699417 DOI: 10.1039/d2cc02565e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
A novel family of cyclic (alkyl)(amino)carbenes, which we name cyclic (amino)(barrelene)carbenes (CABCs) is reported. The key synthetic step involves an intramolecular [4+2] cyclization of an anthracene derivative with an alkyne. This synthetic approach allows for the attachment of both aryl and alkyl groups on the nitrogen atom. When used as ligand, two of the barrelene hydrogens are in close contact with the metal, which could stabilize low valent catalytic intermediates.
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Affiliation(s)
- Melinda R Serrato
- UCSD-CNRS Joint Research Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California, 92093, USA.
| | - Mohand Melaimi
- UCSD-CNRS Joint Research Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California, 92093, USA.
| | - Guy Bertrand
- UCSD-CNRS Joint Research Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California, 92093, USA.
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16
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Thiazol-2-ylidenes as N-Heterocyclic carbene ligands with enhanced electrophilicity for transition metal catalysis. Commun Chem 2022; 5:60. [PMID: 36697942 PMCID: PMC9814509 DOI: 10.1038/s42004-022-00675-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 04/21/2022] [Indexed: 01/28/2023] Open
Abstract
Over the last 20 years, N-heterocyclic carbenes (NHCs) have emerged as a dominant direction in ligand development in transition metal catalysis. In particular, strong σ-donation in combination with tunable steric environment make NHCs to be among the most common ligands used for C-C and C-heteroatom bond formation. Herein, we report the study on steric and electronic properties of thiazol-2-ylidenes. We demonstrate that the thiazole heterocycle and enhanced π-electrophilicity result in a class of highly active carbene ligands for electrophilic cyclization reactions to form valuable oxazoline heterocycles. The evaluation of steric, electron-donating and π-accepting properties as well as structural characterization and coordination chemistry is presented. This mode of catalysis can be applied to late-stage drug functionalization to furnish attractive building blocks for medicinal chemistry. Considering the key role of N-heterocyclic ligands, we anticipate that N-aryl thiazol-2-ylidenes will be of broad interest as ligands in modern chemical synthesis.
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17
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Zhang J, Wang Y, Zhang Y, Liu T, Fang S, Wang R, Ma Y, Fang R, Szostak R, Szostak M. Application of Indazolin-3-ylidenes in Catalysis: Steric Tuning of Nonclassical Formally Normal N-Heterocyclic Carbenes with Dual Electronic Character for Catalysis. Organometallics 2022. [DOI: 10.1021/acs.organomet.2c00140] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jin Zhang
- College of Chemistry and Chemical Engineering, Key Laboratory of Chemical Additives for China National Light Industry, Shaanxi University of Science and Technology, Xi’an 710021, China
| | - Yue Wang
- College of Chemistry and Chemical Engineering, Key Laboratory of Chemical Additives for China National Light Industry, Shaanxi University of Science and Technology, Xi’an 710021, China
| | - Yuting Zhang
- College of Chemistry and Chemical Engineering, Key Laboratory of Chemical Additives for China National Light Industry, Shaanxi University of Science and Technology, Xi’an 710021, China
| | - Ting Liu
- College of Chemistry and Chemical Engineering, Key Laboratory of Chemical Additives for China National Light Industry, Shaanxi University of Science and Technology, Xi’an 710021, China
| | - Shuai Fang
- College of Chemistry and Chemical Engineering, Key Laboratory of Chemical Additives for China National Light Industry, Shaanxi University of Science and Technology, Xi’an 710021, China
| | - Ruihong Wang
- Institute of Frontier Science and Technology Transfer, Shaanxi University of Science and Technology, Xi’an 710021, China
| | - Yangmin Ma
- College of Chemistry and Chemical Engineering, Key Laboratory of Chemical Additives for China National Light Industry, Shaanxi University of Science and Technology, Xi’an 710021, China
| | - Ran Fang
- College of Chemistry and Chemical Engineering, Key Laboratory of Chemical Additives for China National Light Industry, Shaanxi University of Science and Technology, Xi’an 710021, China
| | - Roman Szostak
- Department of Chemistry, Wroclaw University, F. Joliot-Curie 14, Wroclaw 50-383, Poland
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
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18
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Ruppert H, Greb L. Calix[4]pyrrolato Stannate(II): A Tetraamido Tin(II) Dianion and Strong Metal‐Centered σ‐Donor. Angew Chem Int Ed Engl 2022; 61:e202116615. [PMID: 35019214 PMCID: PMC9306640 DOI: 10.1002/anie.202116615] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Indexed: 01/07/2023]
Abstract
Anionic, metal‐centered nucleophiles are emerging compounds with unique reactivities. Here, we describe the isolation and full characterization of the first tetraamido tin(II) dianion, its behavior as ligand towards transition metals, and its reactivity as a tin‐centered nucleophile. Experimental values such as the Tolman electronic parameter (TEP) and computations attest tin‐located σ‐donor ability exceeding that of carbenes or electron‐rich phosphines. Against transition metals, the stannate(II) can act as η1‐ or η5‐type ligand. With aldehydes, it reacts by hydride substitution to give valuable acyl stannates. The reductive dehalogenation of iodobenzene indicates facile redox pathways mediated by halogen bond interaction. Calix[4]pyrrolato stannate(II) represents the first example of this macrocyclic ligand in low‐valent p‐block element chemistry.
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Affiliation(s)
- Heiko Ruppert
- Anorganisch-Chemisches Institut Ruprecht-Karls-Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
| | - Lutz Greb
- Department of Chemistry and Biochemistry - Inorganic Chemistry Freie Universität Berlin Fabeckstr. 34/36 14195 Berlin Germany
- Anorganisch-Chemisches Institut Ruprecht-Karls-Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
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19
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Termühlen S, Dutschke PD, Hepp A, Hahn E. Steric and Electronic Properties of Indol‐Derived CAAC Ligands. Eur J Inorg Chem 2022. [DOI: 10.1002/ejic.202101065] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Sebastian Termühlen
- Westfälische Wilhelms-Universität Münster: Westfalische Wilhelms-Universitat Munster Chemistry GERMANY
| | - Patrick D. Dutschke
- Westfälische Wilhelms-Universität Münster: Westfalische Wilhelms-Universitat Munster Chemistry GERMANY
| | - Alexander Hepp
- Westfälische Wilhelms-Universität Münster: Westfalische Wilhelms-Universitat Munster Chemistry GERMANY
| | - Ekkehardt Hahn
- Westfalische Wilhelms Universitat Munster Department of Chemistry Corrensstraße 30 48149 Münster GERMANY
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20
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Bakhonsky VV, Becker J, Mlostoń G, Schreiner PR. N-Alkoxyimidazolylidines (NOHCs): nucleophilic carbenes based on an oxidized imidazolium core. Chem Commun (Camb) 2022; 58:1538-1541. [PMID: 35006231 DOI: 10.1039/d1cc05696d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
We report the first preparation of N-alkoxyimidazolylidene (NOHC), a nucleophilic carbene based on an oxidized imidazolium core. The Arduengo-type analogous carbene center shows the most upfield 13C NMR shift compared to common NHCs. The obtained gold(I) complex of the carbene follows the 13C NMR upfield trend and shows the marked influence the alkoxy substituents. Similarly, the 77Se and 15N NMR shifts of a range of NOHC-selenium adducts show increased σ-donation and decreased π-back donation in the bonding with the nucleophile. This extension of the NHC family provides altered electronic properties for the use of such carbenes as ligands or catalysts.
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Affiliation(s)
- Vladyslav V Bakhonsky
- Institute of Organic Chemistry, Justus Liebig University, Heinrich-Buff-Ring 17,, 35392 Giessen, Germany. .,Department of Organic Chemistry, National Technical University of Ukraine "Igor Sikorsky Kyiv Polytechnic Institute", Prosp. Peremohy 37, 03056 Kyiv, Ukraine
| | - Jonathan Becker
- Institute of Inorganic and Analytical Chemistry, Justus Liebig University, Heinrich-Buff-Ring 17, 35392 Giessen, Germany
| | - Grzegorz Mlostoń
- Department of Organic and Applied Chemistry, University of Łódź, Tamka 12, PL-91-403 Łódź, Poland
| | - Peter R Schreiner
- Institute of Organic Chemistry, Justus Liebig University, Heinrich-Buff-Ring 17,, 35392 Giessen, Germany.
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21
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D̵ord̵ević N, Huynh HV. Stereoelectronic Evaluation of Pyrazole- and Indazole-Derived N-Heterocyclic Carbenes. Organometallics 2022. [DOI: 10.1021/acs.organomet.1c00675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Nemanja D̵ord̵ević
- Department of Chemistry, Faculty of Science, National University of Singapore, 3 Science Drive 3, Singapore 117453, Republic of Singapore
| | - Han Vinh Huynh
- Department of Chemistry, Faculty of Science, National University of Singapore, 3 Science Drive 3, Singapore 117453, Republic of Singapore
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22
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Ruppert H, Greb L. Calix[4]pyrrolato Stannate(II): A Tetraamido Tin(II) Dianion and Strong Metal‐Centered σ‐Donor. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202116615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Heiko Ruppert
- Ruprecht Karls Universität Heidelberg: Ruprecht Karls Universitat Heidelberg Anorganisch-Chemisches Institut GERMANY
| | - Lutz Greb
- Freie Universitat Berlin Institut für Chemie und Biochemie, Anorganische Chemie Institut für Anorganische ChemieFabeckstr. 34-36 14195 Berlin GERMANY
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23
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Cyclic (alkyl)(amino)carbene (CAAC) ligands: Electronic structure and application as chemically- and redox-non-innocent ligands and chromophores. ADVANCES IN ORGANOMETALLIC CHEMISTRY 2022. [DOI: 10.1016/bs.adomc.2022.03.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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24
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Byun S, Park DA, Kim S, Kim S, Ryu JY, Lee J, Hong S. Highly selective ethenolysis with acyclic-aminooxycarbene ruthenium catalysts. Inorg Chem Front 2022. [DOI: 10.1039/d1qi01132d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Acyclic carbene–ruthenium catalysts were developed for the ethenolysis. Remarkable catalytic efficiency (turnover numbers of 100 000) and excellent α-olefin selectivity (up to 98%) were exhibited.
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Affiliation(s)
- Seunghwan Byun
- Department of Chemistry, Gwangju Institute of Science and Technology, 123 Cheomdan-gwagiro, Buk-gu, Gwangju 61005, Republic of Korea
- Grubbs Center for Polymers and Catalysis, Gwangju Institute of Science and Technology, 123 Cheomdan-gwagi-ro, Buk-gu, Gwangju 61005, Republic of Korea
| | - Da-Ae Park
- Department of Chemistry, Gwangju Institute of Science and Technology, 123 Cheomdan-gwagiro, Buk-gu, Gwangju 61005, Republic of Korea
| | - Seyong Kim
- Department of Chemistry, Gwangju Institute of Science and Technology, 123 Cheomdan-gwagiro, Buk-gu, Gwangju 61005, Republic of Korea
| | - Sunghyun Kim
- Department of Chemistry, Gwangju Institute of Science and Technology, 123 Cheomdan-gwagiro, Buk-gu, Gwangju 61005, Republic of Korea
| | - Ji Yeon Ryu
- Department of Chemistry, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 61186, Republic of Korea
| | - Junseong Lee
- Department of Chemistry, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 61186, Republic of Korea
| | - Sukwon Hong
- Department of Chemistry, Gwangju Institute of Science and Technology, 123 Cheomdan-gwagiro, Buk-gu, Gwangju 61005, Republic of Korea
- Grubbs Center for Polymers and Catalysis, Gwangju Institute of Science and Technology, 123 Cheomdan-gwagi-ro, Buk-gu, Gwangju 61005, Republic of Korea
- School of Materials Science and Engineering, Gwangju Institute of Science and Technology, 123 Cheomdan-gwagiro, Buk-gu, Gwangju 61005, Republic of Korea
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25
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Barnett C, Cole ML, Harper JB. Steric Properties of
N
‐Heterocyclic Carbenes affect the Performance of Electronic Probes. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100796] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Christopher Barnett
- School of Chemistry University of New South Wales UNSW Sydney NSW 2052 Sydney Australia
- School of Chemistry The University of Sydney Sydney NSW 2006 Australia
| | - Marcus L. Cole
- School of Chemistry University of New South Wales UNSW Sydney NSW 2052 Sydney Australia
| | - Jason B. Harper
- School of Chemistry University of New South Wales UNSW Sydney NSW 2052 Sydney Australia
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26
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Ho LP, Neitzel A, Bannenberg T, Tamm M. Rhodium and Iridium Complexes of Anionic Thione and Selone Ligands Derived from Anionic N-Heterocyclic Carbenes. Chemistry 2021; 28:e202104139. [PMID: 34878696 PMCID: PMC9305287 DOI: 10.1002/chem.202104139] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Indexed: 11/21/2022]
Abstract
The lithium salts of anionic N‐heterocyclic thiones and selones [{(WCA‐IDipp)E}Li(toluene)] (1: E=S; 2: E=Se; WCA=B(C6F5)3, IDipp=1,3‐bis(2,6‐diisopropylphenyl)imidazolin‐2‐ylidene), which contain a weakly coordinating anionic (WCA) borate moiety in the imidazole backbone were reacted with Me3SiCl, to furnish the silylated adducts (WCA‐IDipp)ESiMe3 (3: E=S; 4: E=Se). The reaction of the latter with [(η5‐C5Me5)MCl2]2 (M=Rh, Ir) afforded the rhodium(III) and iridium(III) half‐sandwich complexes [{(WCA‐IDipp)E}MCl(η5‐C5Me5)] (5–8). The direct reaction of the lithium salts 1 and 2 with a half or a full equivalent of [M(COD)Cl]2 (M=Rh, Ir) afforded the monometallic complexes [{(WCA‐IDipp)E}M(COD)] (9–12) or the bimetallic complexes [μ2‐{(WCA‐IDipp)E}M2(COD)2(μ2‐Cl)] (13–16), respectively. The bonding situation in these complexes has been investigated by means of density functional theory (DFT) calculations, revealing thiolate or selenolate ligand character with negligible metal‐chalcogen π‐interaction.
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Affiliation(s)
- Luong Phong Ho
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106, Braunschweig, Germany
| | - Angelika Neitzel
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106, Braunschweig, Germany
| | - Thomas Bannenberg
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106, Braunschweig, Germany
| | - Matthias Tamm
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106, Braunschweig, Germany
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27
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Hu C, Huang S, Zhang Z, Yao H, Wu Y, Huang L, Yan X. Experimental and Computational Study on Photophysical Properties of Mesoionic Chalcogenones. Chem Asian J 2021; 16:4165-4170. [PMID: 34729937 DOI: 10.1002/asia.202101157] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 10/30/2021] [Indexed: 12/14/2022]
Abstract
N-Heterocyclic carbene adducts with main group elements (NHC=E) have aroused great interest and have been widely investigated in coordination chemistry. Among them, N-heterocyclic carbene adducts with chalcogens (NHC=Ch) have been known for a long time. Their investigations mostly focused on synthesis, coordination chemistry and electrochemistry. Their photophysical properties still remain unexplored. In this work, the photophysical properties of mesoionic carbene adducts with sulfur and selenium have been investigated both in solution and solid state. These compounds showed blue fluorescence in dichloromethane. While in solid state, orange to red room-temperature phosphorescence can be observed, and dual emission was found in mesoionic thiones. Furthermore, time-dependent density functional theory (TD-DFT) calculations were used to obtain insights into the luminescent mechanism.
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Affiliation(s)
- Chubin Hu
- Key Laboratory of Advanced Light Conversion Materials and Biophotonics, Department of Chemistry, Renmin University of China, Beijing, 100872, P. R. China
| | - Shiqing Huang
- Key Laboratory of Advanced Light Conversion Materials and Biophotonics, Department of Chemistry, Renmin University of China, Beijing, 100872, P. R. China
| | - Zengyu Zhang
- Key Laboratory of Advanced Light Conversion Materials and Biophotonics, Department of Chemistry, Renmin University of China, Beijing, 100872, P. R. China
| | - Haidan Yao
- Key Laboratory of Advanced Light Conversion Materials and Biophotonics, Department of Chemistry, Renmin University of China, Beijing, 100872, P. R. China
| | - Yixin Wu
- Key Laboratory of Advanced Light Conversion Materials and Biophotonics, Department of Chemistry, Renmin University of China, Beijing, 100872, P. R. China
| | - Linwei Huang
- Key Laboratory of Advanced Light Conversion Materials and Biophotonics, Department of Chemistry, Renmin University of China, Beijing, 100872, P. R. China
| | - Xiaoyu Yan
- Key Laboratory of Advanced Light Conversion Materials and Biophotonics, Department of Chemistry, Renmin University of China, Beijing, 100872, P. R. China
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28
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Mikhaylov VN, Balova IA. Alternative Transformations of N-Heterocyclic Carbene Complexes of the Group 11 Metals in Transmetalation Reactions (A Review). RUSS J GEN CHEM+ 2021. [DOI: 10.1134/s1070363221110098] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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29
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Hanusch F, Munz D, Sutter J, Meyer K, Inoue S. A Zwitterionic Heterobimetallic Gold-Iron Complex Supported by Bis(N-Heterocyclic Imine)Silyliumylidene. Angew Chem Int Ed Engl 2021; 60:23274-23280. [PMID: 34411406 PMCID: PMC8596601 DOI: 10.1002/anie.202108146] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Indexed: 01/15/2023]
Abstract
The facile synthesis of the first bis-N-heterocyclic imine-stabilized chlorosilyliumylidene 1 is reported. Remarkably, consecutive reaction of 1 with PPh3 AuCl and K2 Fe(CO)4 gives rise to the unique heterobimetallic complex 1,2-(Mes NHI)2 -C2 H4 -ClSiAuFe(CO)4 (4). The overall neutral complex 4 bears an unusual linear Si-Au-Fe structure and a rare anagostic interaction between the d10 -configured gold atom and a CH bond of the mesityl ligand. According to the computational analysis and 57 Fe Mössbauer spectroscopy, the formal Fe-oxidation state remains at -II. Thus, the electronic structure of 4 is best described as an overall neutral-yet zwitterionic-heterobimetallic "Si(II)+ -Au(I)+ -Fe(-II)2- "-silyliumylidene complex, derived from double anion exchange. The computational analysis indicates strong hyperconjugative back donation from the gold(I) atom to the silyliumylidene ligand.
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Affiliation(s)
- Franziska Hanusch
- Department of ChemistryCatalysis Research Center and Institute of Silicon ChemistryTechnische Universität München (TUM)Lichtenbergstrasse 485748Garching bei MünchenGermany
| | - Dominik Munz
- Faculty of Natural Sciences and TechnologyInorganic Chemistry: Coordination ChemistrySaarland UniversityCampus C4 166123SaarbrückenGermany
- Department of Chemistry and PharmacyInorganic ChemistryFriedrich-Alexander-Universität Erlangen-Nürnberg (FAU)Egerlandstrasse 191058ErlangenGermany
| | - Jörg Sutter
- Department of Chemistry and PharmacyInorganic ChemistryFriedrich-Alexander-Universität Erlangen-Nürnberg (FAU)Egerlandstrasse 191058ErlangenGermany
| | - Karsten Meyer
- Department of Chemistry and PharmacyInorganic ChemistryFriedrich-Alexander-Universität Erlangen-Nürnberg (FAU)Egerlandstrasse 191058ErlangenGermany
| | - Shigeyoshi Inoue
- Department of ChemistryCatalysis Research Center and Institute of Silicon ChemistryTechnische Universität München (TUM)Lichtenbergstrasse 485748Garching bei MünchenGermany
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30
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Mames A, Pietrzak M, Bernatowicz P, Kubas A, Luboradzki R, Ratajczyk T. NMR Crystallography Enhanced by Quantum Chemical Calculations and Liquid State NMR Spectroscopy for the Investigation of Se-NHC Adducts*. Chemistry 2021; 27:16477-16487. [PMID: 34606111 DOI: 10.1002/chem.202102800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Indexed: 11/11/2022]
Abstract
N-heterocyclic carbene ligands (NHC) are widely utilized in catalysis and material science. They are characterized by their steric and electronic properties. Steric properties are usually quantified on the basis of their static structure, which can be determined by X-ray diffraction. The electronic properties are estimated in the liquid state; for example, via the 77 Se liquid state NMR of Se-NHC adducts. We demonstrate that 77 Se NMR crystallography can contribute to the characterization of the structural and electronic properties of NHC in solid and liquid states. Selected Se-NHC adducts are investigated via 77 Se solid state NMR and X-ray crystallography, supported by quantum chemical calculations. This investigation reveals a correlation between the molecular structure of adducts and NMR parameters, including not only isotropic chemical shifts but also the other chemical shift tensor components. Afterwards, the liquid state 77 Se NMR data is presented and interpreted in terms of the quantum chemistry modelling. The discrepancy between the structural and electronic properties, and in particular the π-accepting abilities of adducts in the solid and liquid states is discussed. Finally, the 13 C isotropic chemical shift from the liquid state NMR and the 13 C tensor components are also discussed, and compared with their 77 Se counterparts. 77 Se NMR crystallography can deliver valuable information about NHC ligands, and together with liquid state 77 Se NMR can provide an in-depth outlook on the properties of NHC ligands.
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Affiliation(s)
- Adam Mames
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland
| | - Mariusz Pietrzak
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland
| | - Piotr Bernatowicz
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland
| | - Adam Kubas
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland
| | - Roman Luboradzki
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland
| | - Tomasz Ratajczyk
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland
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31
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Hanusch F, Munz D, Sutter J, Meyer K, Inoue S. A Zwitterionic Heterobimetallic Gold–Iron Complex Supported by Bis(
N
‐Heterocyclic Imine)Silyliumylidene. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202108146] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Franziska Hanusch
- Department of Chemistry Catalysis Research Center and Institute of Silicon Chemistry Technische Universität München (TUM) Lichtenbergstrasse 4 85748 Garching bei München Germany
| | - Dominik Munz
- Faculty of Natural Sciences and Technology Inorganic Chemistry: Coordination Chemistry Saarland University Campus C4 1 66123 Saarbrücken Germany
- Department of Chemistry and Pharmacy Inorganic Chemistry Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) Egerlandstrasse 1 91058 Erlangen Germany
| | - Jörg Sutter
- Department of Chemistry and Pharmacy Inorganic Chemistry Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) Egerlandstrasse 1 91058 Erlangen Germany
| | - Karsten Meyer
- Department of Chemistry and Pharmacy Inorganic Chemistry Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) Egerlandstrasse 1 91058 Erlangen Germany
| | - Shigeyoshi Inoue
- Department of Chemistry Catalysis Research Center and Institute of Silicon Chemistry Technische Universität München (TUM) Lichtenbergstrasse 4 85748 Garching bei München Germany
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32
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Gao Y, Yazdani S, Kendrick A, Junor GP, Kang T, Grotjahn DB, Bertrand G, Jazzar R, Engle KM. Cyclic (Alkyl)(amino)carbene Ligands Enable Cu‐Catalyzed Markovnikov Protoboration and Protosilylation of Terminal Alkynes: A Versatile Portal to Functionalized Alkenes**. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202106107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Yang Gao
- Department of Chemistry The Scripps Research Institute 10550 N Torrey Pines Road La Jolla CA 92037-1000 USA
| | - Sima Yazdani
- Department of Chemistry and Biochemistry University of California, San Diego UCSD-CNRS Joint Research Laboratory (IRL 3555) La Jolla CA 92093-0358 USA
- Department of Chemistry and Biochemistry San Diego State University 5500 Campanile Drive San Diego CA 92182-1030 USA
| | - Aaron Kendrick
- Department of Chemistry The Scripps Research Institute 10550 N Torrey Pines Road La Jolla CA 92037-1000 USA
| | - Glen P. Junor
- Department of Chemistry and Biochemistry University of California, San Diego UCSD-CNRS Joint Research Laboratory (IRL 3555) La Jolla CA 92093-0358 USA
| | - Taeho Kang
- Department of Chemistry The Scripps Research Institute 10550 N Torrey Pines Road La Jolla CA 92037-1000 USA
| | - Douglas B. Grotjahn
- Department of Chemistry and Biochemistry San Diego State University 5500 Campanile Drive San Diego CA 92182-1030 USA
| | - Guy Bertrand
- Department of Chemistry and Biochemistry University of California, San Diego UCSD-CNRS Joint Research Laboratory (IRL 3555) La Jolla CA 92093-0358 USA
| | - Rodolphe Jazzar
- Department of Chemistry and Biochemistry University of California, San Diego UCSD-CNRS Joint Research Laboratory (IRL 3555) La Jolla CA 92093-0358 USA
| | - Keary M. Engle
- Department of Chemistry The Scripps Research Institute 10550 N Torrey Pines Road La Jolla CA 92037-1000 USA
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33
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Dong Z, Blaskovits JT, Fadaei-Tirani F, Scopelliti R, Sienkiewicz A, Corminboeuf C, Severin K. Tuning the π-Accepting Properties of Mesoionic Carbenes: A Combined Computational and Experimental Study. Chemistry 2021; 27:11983-11988. [PMID: 34105837 PMCID: PMC8456875 DOI: 10.1002/chem.202101742] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Indexed: 02/02/2023]
Abstract
Mesoionic imidazolylidenes are recognized as excellent electron‐donating ligands in organometallic and main group chemistry. However, these carbene ligands typically show poor π‐accepting properties. A computational analysis of 71 mesoionic imidazolylidenes that bear different aryl or heteroaryl substituents in C2 position was performed. The study has revealed that a diphenyltriazinyl (Dpt) substituent renders the corresponding carbene particularly π‐acidic. The computational results could be corroborated experimentally. A mesoionic imidazolylidene with a Dpt substituent was found to be a better σ‐donor and a better π‐acceptor compared to an Arduengo‐type N‐heterocyclic carbene. To demonstrate the utility of the new carbene, the ligand was used to stabilize a low‐valent paramagnetic tin compound.
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Affiliation(s)
- Zhaowen Dong
- Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - J Terence Blaskovits
- Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Farzaneh Fadaei-Tirani
- Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Rosario Scopelliti
- Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Andrzej Sienkiewicz
- Institute of Physics, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland.,ADSresonances Sarl, Route de Genève 60B, 1028, Préverenges, Switzerland
| | - Clémence Corminboeuf
- Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Kay Severin
- Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
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34
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Zhao Q, Meng G, Li G, Flach C, Mendelsohn R, Lalancette R, Szostak R, Szostak M. IPr# - highly hindered, broadly applicable N-heterocyclic carbenes. Chem Sci 2021; 12:10583-10589. [PMID: 34447551 PMCID: PMC8356752 DOI: 10.1039/d1sc02619d] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 06/28/2021] [Indexed: 12/15/2022] Open
Abstract
IPr (IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) represents the most important NHC (NHC = N-heterocyclic carbene) ligand throughout the field of homogeneous catalysis. Herein, we report the synthesis, catalytic activity, and full structural and electronic characterization of novel, sterically-bulky, easily-accessible NHC ligands based on the hash peralkylation concept, including IPr#, Np# and BIAN-IPr#. The new ligands have been commercialized in collaboration with Millipore Sigma: IPr#HCl, 915653; Np#HCl; 915912; BIAN-IPr#HCl, 916420, enabling broad access of the academic and industrial researchers to new ligands for reaction optimization and screening. In particular, the synthesis of IPr# hinges upon cost-effective, modular alkylation of aniline, an industrial chemical that is available in bulk. The generality of this approach in ligand design is demonstrated through facile synthesis of BIAN-IPr# and Np#, two ligands that differ in steric properties and N-wingtip arrangement. The broad activity in various cross-coupling reactions in an array of N–C, O–C, C–Cl, C–Br, C–S and C–H bond cross-couplings is demonstrated. The evaluation of steric, electron-donating and π-accepting properties as well as coordination chemistry to Au(i), Rh(i) and Pd(ii) is presented. Given the tremendous importance of NHC ligands in homogenous catalysis, we expect that this new class of NHCs will find rapid and widespread application. We report novel, sterically-bulky, easily-accessible NHC ligands based on the hash peralkylation concept. The new ligands have been commercialized in collaboration with Millipore Sigma: IPr#HCl, 915653; Np#HCl; 915912; BIAN-IPr#HCl, 916420.![]()
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Affiliation(s)
- Qun Zhao
- Department of Chemistry, Rutgers University 73 Warren Street Newark NJ 07102 USA
| | - Guangrong Meng
- Department of Chemistry, Rutgers University 73 Warren Street Newark NJ 07102 USA
| | - Guangchen Li
- Department of Chemistry, Rutgers University 73 Warren Street Newark NJ 07102 USA
| | - Carol Flach
- Department of Chemistry, Rutgers University 73 Warren Street Newark NJ 07102 USA
| | - Richard Mendelsohn
- Department of Chemistry, Rutgers University 73 Warren Street Newark NJ 07102 USA
| | - Roger Lalancette
- Department of Chemistry, Rutgers University 73 Warren Street Newark NJ 07102 USA
| | - Roman Szostak
- Department of Chemistry, Wroclaw University F. Joliot-Curie 14 Wroclaw 50-383 Poland
| | - Michal Szostak
- Department of Chemistry, Rutgers University 73 Warren Street Newark NJ 07102 USA
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35
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Zapf L, Radius U, Finze M. 1,3-Bis(tricyanoborane)imidazoline-2-ylidenate Anion-A Ditopic Dianionic N-Heterocyclic Carbene Ligand. Angew Chem Int Ed Engl 2021; 60:17974-17980. [PMID: 33961330 PMCID: PMC8453866 DOI: 10.1002/anie.202105529] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Indexed: 01/14/2023]
Abstract
The 1,3-bis(tricyanoborane)imidazolate anion 1 was obtained in high yield from lithium imidazolate and B(CN)3 -pyridine adduct. Anion 1 is chemically very robust and thus allowed the isolation of the corresponding H5 O2 + salt. Furthermore, monoanion 1 served as starting species for the novel dianionic N-heterocyclic carbene (NHC), 1,3-bis(tricyanoborane)imidazoline-2-ylidenate anion 3 that acts as ditopic ligand via the carbene center and the cyano groups at boron. First reactions of this new NHC 3 with methyl iodide, elemental selenium, and [Ni(CO)4 ] led to the methylated imidazolate ion 4, the dianionic selenium adduct 5, and the dianionic nickel tricarbonyl complex 6. These NHC derivatives provide a first insight into the electronic and steric properties of the dianionic NHC 3. Especially the combination of properties, such as double negative charge, different coordination sites, large buried volume and good σ-donor and π-acceptor ability, make NHC 3 a unique and promising ligand and building block.
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Affiliation(s)
- Ludwig Zapf
- Institut für nachhaltige Chemie & Katalyse mit Bor (ICB)Institut für Anorganische ChemieJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Udo Radius
- Institut für nachhaltige Chemie & Katalyse mit Bor (ICB)Institut für Anorganische ChemieJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Maik Finze
- Institut für nachhaltige Chemie & Katalyse mit Bor (ICB)Institut für Anorganische ChemieJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
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36
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Zapf L, Radius U, Finze M. Das 1,3‐Bis(tricyanoboran)imidazolin‐2‐ylidenat‐Anion – Ein ditopischer dianionischer N‐heterocyclischer Carben‐Ligand. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202105529] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Ludwig Zapf
- Institut für nachhaltige Chemie & Katalyse mit Bor (ICB) Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Udo Radius
- Institut für nachhaltige Chemie & Katalyse mit Bor (ICB) Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Maik Finze
- Institut für nachhaltige Chemie & Katalyse mit Bor (ICB) Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
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37
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Gao Y, Yazdani S, Kendrick A, Junor GP, Kang T, Grotjahn DB, Bertrand G, Jazzar R, Engle KM. Cyclic (Alkyl)(amino)carbene Ligands Enable Cu-Catalyzed Markovnikov Protoboration and Protosilylation of Terminal Alkynes: A Versatile Portal to Functionalized Alkenes*. Angew Chem Int Ed Engl 2021; 60:19871-19878. [PMID: 34159696 DOI: 10.1002/anie.202106107] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 06/11/2021] [Indexed: 12/19/2022]
Abstract
Regioselective hydrofunctionalization of alkynes represents a straightforward route to access alkenyl boronate and silane building blocks. In previously reported catalytic systems, high selectivity is achieved with a limited scope of substrates and/or reagents, with general solutions lacking. Herein, we describe a selective copper-catalyzed Markovnikov hydrofunctionalization of terminal alkynes that is facilitated by strongly donating cyclic (alkyl)(amino)carbene (CAAC) ligands. Using this method, both alkyl- and aryl-substituted alkynes are coupled with a variety of boryl and silyl reagents with high α-selectivity. The reaction is scalable, and the products are versatile intermediates that can participate in various downstream transformations. Preliminary mechanistic experiments shed light on the role of CAAC ligands in this process.
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Affiliation(s)
- Yang Gao
- Department of Chemistry, The Scripps Research Institute, 10550 N Torrey Pines Road, La Jolla, CA, 92037-1000, USA
| | - Sima Yazdani
- Department of Chemistry and Biochemistry, University of California, San Diego, UCSD-CNRS Joint Research Laboratory (IRL 3555), La Jolla, CA, 92093-0358, USA.,Department of Chemistry and Biochemistry, San Diego State University, 5500 Campanile Drive, San Diego, CA, 92182-1030, USA
| | - Aaron Kendrick
- Department of Chemistry, The Scripps Research Institute, 10550 N Torrey Pines Road, La Jolla, CA, 92037-1000, USA
| | - Glen P Junor
- Department of Chemistry and Biochemistry, University of California, San Diego, UCSD-CNRS Joint Research Laboratory (IRL 3555), La Jolla, CA, 92093-0358, USA
| | - Taeho Kang
- Department of Chemistry, The Scripps Research Institute, 10550 N Torrey Pines Road, La Jolla, CA, 92037-1000, USA
| | - Douglas B Grotjahn
- Department of Chemistry and Biochemistry, San Diego State University, 5500 Campanile Drive, San Diego, CA, 92182-1030, USA
| | - Guy Bertrand
- Department of Chemistry and Biochemistry, University of California, San Diego, UCSD-CNRS Joint Research Laboratory (IRL 3555), La Jolla, CA, 92093-0358, USA
| | - Rodolphe Jazzar
- Department of Chemistry and Biochemistry, University of California, San Diego, UCSD-CNRS Joint Research Laboratory (IRL 3555), La Jolla, CA, 92093-0358, USA
| | - Keary M Engle
- Department of Chemistry, The Scripps Research Institute, 10550 N Torrey Pines Road, La Jolla, CA, 92037-1000, USA
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38
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Menia D, Kopacka H, Wurst K, Müller T, Lippmann P, Ott I, Bildstein B. Cobaltoceniumselenolate Gold(I) Complexes: Synthesis, Spectroscopic, Structural and Anticancer Properties. Eur J Inorg Chem 2021; 2021:2784-2786. [PMID: 34413703 PMCID: PMC8362036 DOI: 10.1002/ejic.202100379] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 05/26/2021] [Indexed: 11/29/2022]
Abstract
Cobaltoceniumselenolate is an unusual, highly air-sensitive, mesoionic compound containing a very soft anionic selenium donor atom. Here we explore its coordination chemistry with Au(I) metal centers and show that its hetero- and homoleptic gold complexes are highly colored, air-stable compounds, which were characterized by 1H/13C/31P/77Se NMR, IR, UV-Vis, HR-MS and single crystal XRD. Cytotoxicity of these polar, water-soluble complexes was studied against various standard cancer cell lines (A549MDA-MB-231, HT-29) revealing good anticancer activity of all three complexes.
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Affiliation(s)
- Daniel Menia
- Institute of General, Inorganic and Theoretical ChemistryUniversity of InnsbruckCenter for Chemistry and BiomedicineInnrain 80–826020InnsbruckAustria
| | - Holger Kopacka
- Institute of General, Inorganic and Theoretical ChemistryUniversity of InnsbruckCenter for Chemistry and BiomedicineInnrain 80–826020InnsbruckAustria
| | - Klaus Wurst
- Institute of General, Inorganic and Theoretical ChemistryUniversity of InnsbruckCenter for Chemistry and BiomedicineInnrain 80–826020InnsbruckAustria
| | - Thomas Müller
- Institute of Organic ChemistryUniversity of InnsbruckCenter for Chemistry and BiomedicineInnrain 80–826020InnsbruckAustria
| | - Petra Lippmann
- Institute of Medicinal and Pharmaceutical ChemistryTechnische Universität BraunschweigBeethovenstr. 5538106BraunschweigGermany
| | - Ingo Ott
- Institute of Medicinal and Pharmaceutical ChemistryTechnische Universität BraunschweigBeethovenstr. 5538106BraunschweigGermany
| | - Benno Bildstein
- Institute of General, Inorganic and Theoretical ChemistryUniversity of InnsbruckCenter for Chemistry and BiomedicineInnrain 80–826020InnsbruckAustria
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39
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Arora A, Oswal P, Kumar Rao G, Kumar S, Kumar A. Organoselenium ligands for heterogeneous and nanocatalytic systems: development and applications. Dalton Trans 2021; 50:8628-8656. [PMID: 33954317 DOI: 10.1039/d1dt00082a] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Organoselenium ligands have attracted great attention among researchers during the past two decades. Various homogeneous, heterogeneous and nanocatalytic systems have been designed using such ligands. Although reports on selenium ligated homogeneous catalysts are quite high in number, significant work has also been done on the development of heterogeneous and nanocatalytic systems using organoselenium ligands. A review article, focusing on the utility of organoselenium compounds in the development of catalytic systems, was published in 2012 (A. Kumar, G. K. Rao, F. Saleem and A. K. Singh, Dalton Trans., 2012, 41, 11949). Moreover, it mainly covered the homogeneous catalysts. There are no review articles in the literature on heterogeneous and nanocatalytic systems designed using organoselenium compounds and their applications. Hence, this perspective aims to cover the developments pertaining to the synthetic aspects of such catalytic systems (using organoselenium compounds) and their applications in catalysis of a variety of chemical transformations. Salient features and advantages of organoselenium compounds have also been highlighted to justify the rationale behind their use in catalyst development. Their performance in various chemical transformations [viz. Suzuki-Miyaura coupling, Heck coupling, Sonogashira coupling, O-arylation of phenol, transfer hydrogenation of aldehydes and ketones, aldehyde-alkyne-amine (A3) coupling, hydration of nitriles, conversion of aldehydes to amides, cross-dehydrogenative coupling (CDC), photodegradation of substrates (formic acid, methylene blue), reduction of nitrophenols, electrolysis (hydrogen evolution reaction and oxygen reduction reactions), organocatalysis and dye sensitized solar cells] and relevant aspects of catalytic processes (such as recyclability, substrate scope and green aspects) have been critically analyzed. Future perspectives have also been discussed.
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Affiliation(s)
- Aayushi Arora
- Department of Chemistry, School of Physical Sciences, Doon University, Dehradun, Uttarakhand 248012, India.
| | - Preeti Oswal
- Department of Chemistry, School of Physical Sciences, Doon University, Dehradun, Uttarakhand 248012, India.
| | - Gyandshwar Kumar Rao
- Department of Chemistry, Amity School of Applied Sciences, Amity University Haryana (AUH), Gurgaon, Haryana 122413, India
| | - Sushil Kumar
- Department of Chemistry, School of Physical Sciences, Doon University, Dehradun, Uttarakhand 248012, India.
| | - Arun Kumar
- Department of Chemistry, School of Physical Sciences, Doon University, Dehradun, Uttarakhand 248012, India.
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40
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Kumar A, Kisan HK, Huynh HV. Reactivity Studies and Electronic Properties of an N-Arylated Acyclic Amino Carbene. Organometallics 2021. [DOI: 10.1021/acs.organomet.1c00181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Anuj Kumar
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543
| | - Hemanta K. Kisan
- Department of Chemistry, Utkal University, Bhubaneswar, Odisha 751004, India
| | - Han Vinh Huynh
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543
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41
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Ho LP, Koneczny M, Bannenberg T, Tamm M. Determination of the π-Accepting Properties of Borate-, Aluminate-, and Gallate-Functionalized N-Heterocyclic Carbenes by 77Se NMR Spectroscopy. Inorg Chem 2021; 60:9019-9028. [DOI: 10.1021/acs.inorgchem.1c01004] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Luong Phong Ho
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106 Brauschweig, Germany
| | - Marvin Koneczny
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106 Brauschweig, Germany
| | - Thomas Bannenberg
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106 Brauschweig, Germany
| | - Matthias Tamm
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106 Brauschweig, Germany
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42
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Su X, Bartholome TA, Tidwell JR, Pujol A, Yruegas S, Martinez JJ, Martin CD. 9-Borafluorenes: Synthesis, Properties, and Reactivity. Chem Rev 2021; 121:4147-4192. [DOI: 10.1021/acs.chemrev.0c01068] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Xiaojun Su
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798, United States
| | - Tyler A. Bartholome
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798, United States
| | - John R. Tidwell
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798, United States
| | - Alba Pujol
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798, United States
| | - Sam Yruegas
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798, United States
| | - Jesse J. Martinez
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798, United States
| | - Caleb D. Martin
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798, United States
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Werner L, Horrer G, Philipp M, Lubitz K, Kuntze‐Fechner MW, Radius U. A General Synthetic Route to NHC‐Phosphinidenes: NHC‐mediated Dehydrogenation of Primary Phosphines. Z Anorg Allg Chem 2021. [DOI: 10.1002/zaac.202000405] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Luis Werner
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Günther Horrer
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Michael Philipp
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Katharina Lubitz
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | | | - Udo Radius
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
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Kim H, Kim M, Song H, Lee E. Indol‐2‐ylidene (IdY): Ambiphilic N‐Heterocyclic Carbene Derived from Indole**. Chemistry 2021; 27:3849-3854. [DOI: 10.1002/chem.202004879] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2020] [Indexed: 12/25/2022]
Affiliation(s)
- Hyunho Kim
- Department of Chemistry Pohang University of Science and Technology Pohang 790-784 Republic of Korea
| | - Minseop Kim
- Department of Chemistry Pohang University of Science and Technology Pohang 790-784 Republic of Korea
| | - Hayoung Song
- Department of Chemistry Pohang University of Science and Technology Pohang 790-784 Republic of Korea
| | - Eunsung Lee
- Department of Chemistry Pohang University of Science and Technology Pohang 790-784 Republic of Korea
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Ghosh M, Panwaria P, Tothadi S, Das A, Khan S. Bis(silanetellurone) with C-H···Te Interaction. Inorg Chem 2020; 59:17811-17821. [PMID: 33215925 DOI: 10.1021/acs.inorgchem.0c03098] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Herein, we report the synthesis of a series of bis(silanechalcogenones) [Ch = Te (2), S (3), or Se (4)] using an N-heterocyclic silylene-based SiCSi pincer ligand (1). 2 is the first example of a bis(silanetellurone) derivative. The bonding patterns of 2-4 were extensively studied by natural bond orbital, quantum theory of atoms in molecules, and noncovalent interaction index analyses, and these exhibit weak C-H···Ch interaction. The analogous reaction of 1 with trimethyl N-oxide produced a novel bis(cyclosiloxane) derivative (5). All of the complexes are duly characterized by single-crystal X-ray diffraction studies, multinuclear nuclear magnetic resonance (1H, 13C, and 29Si) spectroscopy, and high-resolution mass spectrometry.
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Affiliation(s)
- Moushakhi Ghosh
- Department of Chemistry, Indian Institute of Science Education and Research Pune, Dr. Homi Bhabha Road, Pashan, Pune 411008, India
| | - Prakash Panwaria
- Department of Chemistry, Indian Institute of Science Education and Research Pune, Dr. Homi Bhabha Road, Pashan, Pune 411008, India
| | - Srinu Tothadi
- Organic Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pashan, Pune 411008, India
| | - Aloke Das
- Department of Chemistry, Indian Institute of Science Education and Research Pune, Dr. Homi Bhabha Road, Pashan, Pune 411008, India
| | - Shabana Khan
- Department of Chemistry, Indian Institute of Science Education and Research Pune, Dr. Homi Bhabha Road, Pashan, Pune 411008, India
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Pinter P, Munz D. Controlling Möbius-Type Helicity and the Excited-State Properties of Cumulenes with Carbenes. J Phys Chem A 2020; 124:10100-10110. [DOI: 10.1021/acs.jpca.0c07940] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Piermaria Pinter
- Department of Chemistry and Pharmacy, General and Inorganic Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 1, 91058 Erlangen, Germany
| | - Dominik Munz
- Inorganic Chemistry: Coordination Chemistry, Saarland University, Campus Geb. C4.1, 66123 Saarbrücken, Germany
- Department of Chemistry and Pharmacy, General and Inorganic Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 1, 91058 Erlangen, Germany
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Beerhues J, Aberhan H, Streit TN, Sarkar B. Probing Electronic Properties of Triazolylidenes through Mesoionic Selones, Triazolium Salts, and Ir-Carbonyl-Triazolylidene Complexes. Organometallics 2020. [DOI: 10.1021/acs.organomet.0c00614] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Julia Beerhues
- Lehrstuhl für Anorganische Koordinationschemie, Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569, Stuttgart, Germany
| | - Hannes Aberhan
- Institut für Chemie und Biochemie, Freie Universität Berlin, Fabeckstraße 34-36, 14195, Berlin, Germany
| | - Tim-Niclas Streit
- Institut für Chemie und Biochemie, Freie Universität Berlin, Fabeckstraße 34-36, 14195, Berlin, Germany
| | - Biprajit Sarkar
- Lehrstuhl für Anorganische Koordinationschemie, Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569, Stuttgart, Germany
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48
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Jamil MSS, Endot NA. Influence of Fluorine Substituents on the Electronic Properties of Selenium- N-Heterocyclic Carbene Compounds. Molecules 2020; 25:molecules25215161. [PMID: 33171911 PMCID: PMC7664287 DOI: 10.3390/molecules25215161] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Revised: 10/21/2020] [Accepted: 10/22/2020] [Indexed: 12/26/2022] Open
Abstract
N-heterocyclic carbenes (NHCs) are common ancillary ligands in organometallic compounds that are used to alter the electronic and steric properties of a metal centre. To date, various NHCs have been synthesised with different electronic properties, which can be done by modifying the backbone or changing the nitrogen substituents group. This study describes a systematic modification of NHCs by the inclusion of fluorine substituents and examines the use of selenium-NHC compounds to measure the π-accepting ability of these fluorinated NHC ligands. Evaluation of the 77Se NMR chemical shifts of the selenium adducts reveals that fluorinated NHCs have higher chemical shifts than the non-fluorinated counterparts, IMes and IPh. Higher 77Se NMR chemical shifts values indicate a stronger π-accepting ability of the NHC ligands. The findings of this study suggest that the presence of fluorine atoms has increased the π-accepting ability of the corresponding NHC ligands. This work supports the advantage of the 77Se NMR chemical shifts of selenium-NHC compounds for assessing the influence of fluorine substituents on NHC ligands.
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Affiliation(s)
- Mohamad Shazwan Shah Jamil
- Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, Johor Bahru 81310 UTM, Johor, Malaysia
- Correspondence: (M.S.S.J.); (N.A.E.)
| | - Nor Azam Endot
- Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, Serdang 43400 UPM, Selangor, Malaysia
- Correspondence: (M.S.S.J.); (N.A.E.)
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